Detection of collagenase activity in oral bacteria.

Collagenolytic activity of 12 species of oral bacteria was assessed using two methods of detection. Except for two species, all bacterial strains tested were capable of degrading at least one general protein substrate. Results of collagenolytic activity in a growth assay indicate that Bacteroides gingivalis is the only bacterium capable of degrading collagen when the substrate is sterilized using ethylene oxide. However, if the substrate is sterilized by autoclaving, in the presence or absence of the growth medium, other bacterial species could be shown to be collagenolytic. Collagenolytic activity was also demonstrated when whole or broken cells were used in a [14C]collagen assay. Results from this assay and from inhibition studies indicate that collagenolytic activity can either be the result of the combined activities of both a specific collagenase and nonspecific proteases (B. gingivalis) or nonspecific proteases only (other strains in this study), although in the latter case, the time taken to hydrolyze collagen can be 10 times longer than with a specific collagenase.